This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This general user proposal represents a joint effort between the Van Duyne and Bushman laboratories at the University Of Pennsylvania School Of Medicine. We propose the use of the Gl Beamline at CI[unreadable]SS to study the synaptic complex formed between HIV Integrase (Il[unreadable], the integrase binding protein called Lens Epithelial Derived Growth Factor (-EDGF), and substrate DNA in solution, using small-angle x-ray scattering (SAXS). This analysis will complement biophysical and biochemical studies already il progress. Using available high resolution crystal structures of the various components, this scattering data will allow us to construct a low resolution model for synapsis, interaction with binding protein, and catalysis with[unreadable]n the nucleoprotein complex. Currently, there is no experimental structure of an IN/DNA complex available.